diff --git a/app/assets/styles/blocks/_cards.scss b/app/assets/styles/blocks/_cards.scss
index fe6c0847..1beee94a 100644
--- a/app/assets/styles/blocks/_cards.scss
+++ b/app/assets/styles/blocks/_cards.scss
@@ -56,10 +56,19 @@
     position: relative;
     overflow: hidden;
     border-radius: var(--border-radius-lg);
+    // An <iframe> is composited in its own layer: `overflow: hidden` + `border-radius` on the
+    // parent does not clip it in Chrome until the layer tree settles after the frame paints,
+    // so the map showed square corners until it loaded and rounded ones after. clip-path is
+    // applied at paint time regardless of compositing, and the iframe carries the radius too.
+    clip-path: inset(0 round var(--border-radius-lg));
+    isolation: isolate;
 
     iframe {
+        display: block;
         width: 100%;
         height: 20rem;
+        border: 0;
+        border-radius: inherit;
     }
 
     .overlay {
diff --git a/app/components/DoxaMapSlot.vue b/app/components/DoxaMapSlot.vue
index bbfb6b4b..754638e5 100644
--- a/app/components/DoxaMapSlot.vue
+++ b/app/components/DoxaMapSlot.vue
@@ -78,19 +78,63 @@ const effectiveConfig = computed(() => {
 }
 @keyframes doxa-map-spin { to { transform: rotate(360deg); } }
 @media (prefers-reduced-motion: reduce) { .doxa-map-spinner { animation: none; } }
+/* ROUNDED MAP CARDS (carried from doxa-maps-build). The slot is a LAYOUT, not a mask: the map sits
+   inside an opaque rounded frame, inset by enough (0.32r, just over the r(1-1/sqrt 2) corner bite) that its
+   own square corner never reaches the rounded edge, and the four corner wedges are PAINTED over it on
+   their own layer. A WebGL canvas is a composited layer that an ancestor's radius does not reliably clip
+   (the corners went square once a map loaded), so clipping alone is not enough. */
 .doxa-map-slot {
+  /* read by the maps inside their shadow DOM, to round the canvas itself */
+  --map-radius: var(--slot-radius, 0px);
+  --map-radius-corners: var(--slot-radius, 0px);
+  --slot-inset: calc(var(--slot-radius, 0px) * 0.32);
+  --slot-radius: 0px;
+  background: var(--slot-corner-bg, var(--color-surface-default, #F3F3F1));
   display: block;
   position: relative;
   width: 100%;
   min-height: 780px;
   aspect-ratio: 16 / 9;
   overflow: hidden;
+  /* clip-path is applied at paint time, so the corners are round from the first frame, before the
+     compositor has a mask layer for the canvas */
+  clip-path: inset(0 round var(--slot-radius));
+  isolation: isolate;
+  will-change: transform;
+  transform: translateZ(0);
 }
+.doxa-map-slot::after {
+  content: '';
+  position: absolute;
+  inset: 0;
+  pointer-events: none;
+  z-index: 4;
+  /* own compositing layer, so the map's GPU layer cannot paint over the wedges */
+  transform: translateZ(0);
+  will-change: transform;
+  backface-visibility: hidden;
+  --corner-tl: var(--slot-radius, 0px);
+  --corner-tr: var(--slot-radius, 0px);
+  --corner-br: var(--slot-radius, 0px);
+  --corner-bl: var(--slot-radius, 0px);
+  --corner-bg: var(--slot-corner-bg, var(--color-surface-default, #F3F3F1));
+  background:
+    radial-gradient(circle at 100% 100%, #0000 calc(var(--corner-tl) - 0.5px), var(--corner-bg) var(--corner-tl)) left    top    / var(--corner-tl) var(--corner-tl) no-repeat,
+    radial-gradient(circle at 0    100%, #0000 calc(var(--corner-tr) - 0.5px), var(--corner-bg) var(--corner-tr)) right   top    / var(--corner-tr) var(--corner-tr) no-repeat,
+    radial-gradient(circle at 0    0,    #0000 calc(var(--corner-br) - 0.5px), var(--corner-bg) var(--corner-br)) right   bottom / var(--corner-br) var(--corner-br) no-repeat,
+    radial-gradient(circle at 100% 0,    #0000 calc(var(--corner-bl) - 0.5px), var(--corner-bg) var(--corner-bl)) left    bottom / var(--corner-bl) var(--corner-bl) no-repeat;
+}
+/* one corner size for every map card; the element's own radius is pinned to the same token */
+.doxa-map-slot.rounded-md,
+.doxa-map-slot.rounded-xlg { --slot-radius: var(--border-radius-lg); border-radius: var(--slot-radius); }
 
 @media (max-width: 768px) {
   .doxa-map-slot {
     min-height: 0;
+    /* twice as tall as wide (80px more map than the 9/16 before it), capped at one screen so the page
+       below stays reachable */
     aspect-ratio: 1 / 2;
+    max-height: 90svh;
   }
 }
 
@@ -98,9 +142,13 @@ const effectiveConfig = computed(() => {
 .doxa-map-slot :deep(doxa-research-map) {
   display: block;
   position: absolute;
-  inset: 0;
-  width: 100%;
-  height: 100%;
+  /* inset inside the rounded frame; the map keeps its stacking to itself so its legend and search
+     (z-index 1000+) cannot paint over the corner wedges */
+  inset: var(--slot-inset, 0px);
+  isolation: isolate;
+  z-index: 0;
+  width: auto;
+  height: auto;
   /* Inherit any border-radius the host page gave the slot (e.g. .rounded-md /
      .rounded-xlg on the research page). Without this, the bare custom element
      paints a rectangular background during the brief window between page
diff --git a/nuxt.config.ts b/nuxt.config.ts
index b3ce0bca..a3271d90 100644
--- a/nuxt.config.ts
+++ b/nuxt.config.ts
@@ -61,6 +61,10 @@ const termsRouteRules = Object.fromEntries(
   ])
 )
 
+// The dx-maps tree the site loads maps from: the same value as runtimeConfig.public.dxMapsBase below, read
+// at build time for the redirect rules.
+const DX_MAPS_TREE = ((process.env.NUXT_PUBLIC_DX_MAPS_BASE ?? '').replace(/\/+$/, '')) || '/dx-maps'
+
 export default defineNuxtConfig({
   // Embeddables (micro-frontends + web-components) have their own Vite builds —
   // Nuxt must not watch or scan their source trees.
@@ -162,6 +166,16 @@ export default defineNuxtConfig({
   },
 
   routeRules: {
+    // OLD MAP LINKS HEAL THEMSELVES (carried from doxa-maps-build): the dx-maps tree used to be served from
+    // this site at /js/doxa-maps/, then /js/doxa-maps-build/ and /embed/doxa-maps-build/. Bookmarks and older
+    // partner embeds 301 to the same path in the tree the site uses now (NUXT_PUBLIC_DX_MAPS_BASE; unset, as on
+    // this drop-in branch, it is this site's own /dx-maps). Bundles that no longer exist in the
+    // tree 404 there, as they would here.
+    '/js/doxa-maps/**': { redirect: { to: `${DX_MAPS_TREE}/**`, statusCode: 301 } },
+    '/js/doxa-maps-build/doxa-maps/**': { redirect: { to: `${DX_MAPS_TREE}/**`, statusCode: 301 } },
+    '/js/doxa-maps-build/assets/**': { redirect: { to: `${DX_MAPS_TREE}/assets/**`, statusCode: 301 } },
+    '/embed/doxa-maps-build/doxa-maps/**': { redirect: { to: `${DX_MAPS_TREE}/**`, statusCode: 301 } },
+    '/embed/doxa-maps-build/assets/**': { redirect: { to: `${DX_MAPS_TREE}/assets/**`, statusCode: 301 } },
     // Content-hashed build assets never change under the same URL — cache forever.
     '/_nuxt/**': { headers: { 'cache-control': 'public, max-age=31536000, immutable' } },
     // Fonts/images use stable filenames, so avoid `immutable`: a 7-day cache